Rhabdomyloysis in Soldiers: Current Return to Duty Controversies

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Rhabdomyloysis in Soldiers Current Return to
Duty Controversies

• LTC Fred H. Brennan, Jr., DO, FAOASM, FAAFP
• COL Francis G. OConnor, MD, MPH, FACSM
• Uniformed Services University of the Health
  Sciences
• Bethesda, MD

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Objectives

• Discuss return-to-duty considerations in the
  soldier who has been treated for exertional
  rhabdomyolysis
• Discuss opportunities for needed research

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Case 1

• Pt is an 18 y/o Marine officer candidate who
  presents to the clinic after being initially
  treated in the field for possible heat stroke
  after falling out of a run . He was described as
  out of it and had an initial rectal temp of 106
  F
• His initial labs demonstrate a urine that dips
  positive for blood and a CK of 50,000 U/L
• Took 14 days for CK to recover
• Sickle cell trait by history

4
Case 2

• Pt is a 32 y/o Marine who presents to the clinic
  with coca-cola urine and severe bilateral
  biceps pain
• Did 10 sets x 20 reps of negatives with 50
  pound hand weights
• His CK is 60,000 U/L and his urine dips positive
  for blood
• No prior history
• Recovered in 5 days
• Highly trained athlete

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Exercise-Induced Rhabdomyolysis

• Is there a distinction between heat and
  exercise-induced rhabdomyolysis?
• Who is the soldier who will require further
  evaluation?
• What is an appropriate evaluation?
• Who can safely return to duty, and under what
  criteria?
• Who requires a permanent profile and referral to
  an MEB?

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Definition

• Acute Exertional Rhabdomyolysis (AER)
• Rhabdomyolysis arising from exercise or exertion
  
• Usually precipitated by running or extreme muscle
  overload activities
• A spectrum illness ranging from insignificant
  asymptomatic muscle injury with minor laboratory
  alterations to fulminant, immediate life
  threatening syndrome

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Factors in the Development of Exertional
Rhabdomyolysis

• Exercise Factors
• Experience and fitness level
• Intensity
• Duration
• Type

• Non-Exercise Factors
• Metabolic myopathies
• Malignant Hyperthermia
• Illness
• Sickle Cell Trait
• High Ambient Temperature
• Drugs

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Return to Duty Guidelines
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Fort Bragg Return to Duty Guidelines

• Three episodes of heat exhaustion in 24 months
  require referral for an MEB.
• Heat stroke/rhabdomyolysis requires an MEB
  referral.
• 3 month temporary profile restricting heat and
  vigorous physical exercise over 15 minutes.
• If successful, extension of profile through next
  summer heat exposure period.

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Exercise-Induced Rhabdomyolysis
Heat-Related
Non-Heat-Related

• Manage as per
• AR 40-501
• Technical Bulletin TB MED/AFPAM 48-152 March 2003

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AR 501 and Army Technical Bulletins

• No isolated paragraph on exertional
  rhabdomyolysis and return to duty.
• Sub-paragraph under Heat illness
• Heat Stroke
• Exertional Rhabdmoyolysis rhabdomyolysis with
  myoglobinuria occurring with exercise-heat stress
  but without the encephalopathy of heat stroke.

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Marine Return to Duty Guideline

• Individually addressed.
• Personal communication with CAPT Scott Flinn,
  Navy Sports Medicine Consultant

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Rhabdomyolysis Plan of Action

• Walter Reed Army Medical Center Rhabdomyolysis
  Panel
• Physiologists
• Anesthesiologists
• Neurologists
• Sports Medicine Specialists
• Tri-Service

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Consensus Panel Conclusions

• No agreement on clinical definition of
  Rhabdomyolysis
• Lack of understanding of basic epidemiology
• Lack of understanding of natural history and
  prognosis
• Lack of clear criteria for who needs in depth
  evaluation
• Lack of consensus on who may or may not require
  removal from ongoing military service

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Exercise-Induced Rhabdomyolysis Heat and
Non-Heat-Related
Risk Stratification
Low Risk
High Risk

• Referral
• Further Evaluation
• Profile Status

Return-to-Duty
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High Risk Individuals

• Delayed recovery (more than a week) when activity
  has been restricted
• Rhabdomyolysis complicated by acute renal failure
  with significant metabolic derangement
• Muscle injury after low to moderate workload
• Personal or family history of rhabdomyolysis
• Personal or family history of recurrent muscle
  cramps

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High Risk Individuals

• Personal history of severe muscle pain
• Personal or family history of malignant
  hyperthermia
• Personal or familiar history of sickle cell trait
  
• Complicated by drug or supplement use (e.g.
  statin, ephedra, steroids, creatine)
• Personal history of heat injury
• CPK peak gt 10,000 U/L

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Low Risk Soldier

• Rapid recovery with exercise restriction
• Physically fit soldier
• No personal and family history of rhabdomyolysis
  or previous reporting of exercise-induced
  severe muscle pain, muscle cramps, or heat injury

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Low Risk Soldier

• Existence of other rhabdomyolysis cases in the
  same training unit
• Involvement of other diagnosed viral or
  infectious disease.

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Field Risk Stratification

• Step Test
• Under evaluation
• Eccentric load
• Risk stratify rhabdomyolysis patients for further
  evaluation

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Case 1 Marine with heat stroke and rhabdomyolysis

• Is there a distinction between heat and
  exercise-induced rhabdomyolysis?
• Still uncertain
• Will this soldier require further evaluation?
• Yes, high CK, prolonged recovery, SS trait
• What is an appropriate evaluation?

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Further Evaluation

• What should further evaluation consist of
• Muscle Myopathy Panel
• McCardles
• AMP deaminase
• CPT2 Deficiency
• EMG
• Sickle cell screen
• Genetic testing
• Ryanodine receptor
• Others still to be determined
• Muscle biopsy
• Forearm contracture test
• Caffeine Halothane contracture test (MH)

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Case 1 Marine with heat stroke and rhabdomyolysis

• Who can safely return to duty, and under what
  criteria?
• Who requires a permanent profile and referral to
  an MEB?
• Will depend on results of advanced tests
• High risk for recurrence

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Case 2 32 yo with biceps pain

• Will this soldier require further evaluation?
• Probably not
• Highly trained
• Rapid recovery
• Severe acute stress with high load
• No prior problems
• Low risk

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Exertional RhabdomyolysisReturn to Duty
Guidelines for the Low Risk Soldier

• Phase 1
• Strict light indoor duty for 72hrs encourage
  oral hydration, salting of food.
• Must sleep eight consecutive hours nightly.
• Must remain in thermally controlled environment.
• Must follow-up in 72 hrs for repeat CPK/UA. When
  CPK/UA has returned to normal, begin Phase 2,
  otherwise remain in Phase 1 and return every 72
  hrs for repeat CPK/UA until normal.
• If persistently abnormal at week 2, refer for
  expert consultation.
• Phase 2
• Begin light-outdoor duty no strenuous physical
  activities.
• Physical activity at own pace and distance.
• Follow-up with care provider in one week. If no
  issues then begin Phase 3.
• Phase 3
• Return to regular outdoor duty and physical
  training.
• Follow-up with care provider as needed.

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Research Plan

• Continued clinical descriptive data
• Development of field tests to ascertain high risk
  individuals
• Development of a recognized center to assist
  clinicians in evaluating high risk individuals
• Retrospective review of prior cases to assist in
  characterizing natural history of rhabdomyolysis

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Conclusions and Recommendations

• Urgent requirements
• Clinical guidelines addressing soldiers at risk
  for recurrent rhabdomyolysis and heat illness
• Clinical guidelines outlining an evidence-based
  return to duty
• Clinical and basic science research elucidating
  the epidemiology, pathophysiology and natural
  history of exertional rhabdomyolysis